Drafting pen



June 15, 1943. F. G. EUANKs DHAFTING PEN Filed Feb. 1a', 1942 GtornegPatented June 15, 1943 DRAFTING PEN Floyd G. Eubanks, Pasadena, Calif.,assigner, by y'direct and rnesne assignments, of thirty-one and onehalfper cent to Francis E. Vaughan,

Pasadena, live per cent to Robert M.'

McManigal, South Pasadena, Calif., six per cent to Edward Floyd Eubanks,six per cent to Philip Robert Eubanks, six per cent to Patricia RoseEubanks, eight per cent to Edward Urner Vaughan, and eight per cent toPhilip Alfred Vaughan, all of Pasadena,Calif.

Application February 18, 1942, Serial No. 431,387

(Cl. 1Z0-109.5)

4 Claims.

My 'invention relates to new and useful improvements in drafting pens.For the purpose ofV illustration, I disclose a drafting pen comprisingblades; said blades being provided with means for controlling theirseparation.

The object of my invention is to provide a drafting pen with bladeswhich can easily be con* struc-ted of high quality material.

Another object of my invention is to so con struct the blades of the penthat they can be widely separated to facilitate the cleaning of theirpoints or nibs. i

Another object of my invention is to provide a pen for a compass, saidpen having means for locking it in a position normal to the drawingsurface.

My invention has other objects which will be evident from a study of thefollowing specification read in connection with the accompanyingdrawing.

Referring to the drawing:

Figure l is a front View of a ruling pen embody-` ing the features of myinvention.

Figure 2 is a section taken on the line 2 2 of Figure l.

Figure 3 is a section taken on the line 3-3 of Figure 2.

Figure 4 shows another embodiment of my invention in which the pen isattached to a compass.

Figure 5 is an enlarged fragmentary section showing the details ofconstruction of the pen shown in Figure 4.

Figure 6 is a section taken on the line 6--6 of Figure 5.

Referring to Figures 1, 2 and 3, the numeral i l indicates a spoolhaving flanges I2, and about which is looped the vsheet steel strip I3.The sheet steel strip I3 can readily be punched from sheet steel stockand then formed in a die to the desired shape. The 4ends of the metalstrip I3 are ground to form the nibs I4 and I5. rThe thumb screw withthumb piece I6 and screw I'I controls the separation of the nibs lll andI5. The screw I'I passes through a clearance hole in the blade I8 and isscrewed through the blade I9. A small bushing 2li is electrically weldedinto the blade I9 to afford additional thickness in order to engagepassing through the spool II and through a hole in the metal strip I3,is screwed into the pen support 22, thus firmly holding the pen to thesupport. Since the screw 2| passes through both the spool I I and themetal strip I3, it effectively prethe threads on the screw -I'I. Thescrew 2l.'

vents said metal strip I3 from slipping about said spool II. The pensupport 22 may be presstted securely into the handle 23 which can b'e ofmetal, plastic, fiber, wood, or other suitable material.

The metal strip 53 is formed in such amanner that the spring pressuretends to separate the nibs Id and l. The thumb screw i6, Il, holds thenibs I, l5, close together as desired, the proximity ol the nibs to eachother controlling the breadth of the line being ruled by the pen.

Although the blades may be formed of any suitable metal strip, I preferto use sheet spring steel of high quality and thereby provide a pen ofexcellent performance and durability. The blades are adapted to bewidely separated, as clearly shown in Figure 2 of the drawing.

Figures 4, 5 and 6 show a modification of my invention adapted to beused on a compass. In this modification the sheet steel strip comprisingthe blades is adjustably mounted on the spool so that the pen can be setin a position normal to the drawing surface and a locking means isprovided to hold the blades in any adjusted position.

As an instance of this arrangement, the parts 2 and 23 are limbs of acompass to which, respectively, extension point 29 and pen 30 areadapted to be attached. The numeral 3| indicates a spool with anges 32,about which is looped a sheet steel strip 33. The upper part of asupporting rod 34 is clamped in the compass limb 28 in the same manneras a pencil lead is held. The lower part of the supporting rod 34 isthreaded and passes through a hole 35 in the steel strip 33 and througha hole in the spool 3I, being firmly held in the latter by means of aset screw 36. A thumb screw 31 is screwed upon the threaded portion ofthe supporting rod 34. Below this thumb screw 3'! is a curved lock plate38, through which also passes the supporting rod 34.

When the thumb screw 31 is loose above the lock plate 38, the sheetsteel strip 33 is released and, since the hole 35 is elongated somewhatabout the periphery of the spool, the sheet steel strip can be slippedabout the spool through a small arc and thus adjusted so that the axisof the pen is perpendicular to the drawing surface. When the thumb screw31 is screwed downward it presses upon the lock plate 38 and thus firmlyholds the steel strip 33 in the position to which it is adjusted inorder to be perpendicular to the drawing surface as the compass legs 2'Iand 28 are closed or spread to describe small or large circles. Themethod by which the pen can be adjusted perpendicularly to the drawingsurface is shown in Figure 5, in which the position of the supportingrod 34 is shown in dotted lines as the instrument is used in describinglarge circles.

The nibs 40 and 4l should be set perpendicular to the line determined bythe tip of the extension point 29 and the point of the pen so that thepen Will draw tangentially. In order to make this adjustment the setscrew 36 can be released and the spool rotated axially about thesupporting rod 34 and into the proper position. The set screw 36 is thentightened.

Figure 6 shows how the compass pen can be adjusted to follow in thedirection of the desired circle.

Other advantages and the use and operation of the drafting pen of myinvention will be readily understood by those skilled in the art towhich the invention appertains. While I have described the form of myinvention which I now `ends to provide the nibs of said pen, a handle,

said strip and said cylindrical member being held together and to thepen handle by means of a screw passed through them and threaded intosaid handle.

fil

2. A pen for drafting compasses comprising a strip of sheet metal loopedat its mid-portion about a cylindrical member and tapered at its ends toprovide nibs, a support extending from said cylindrical member throughan opening in the looped mid-portion of said strip, said strip beingadjustable about the axis oi said cylindrical member, and means on saidsupport for locking said strip against movement about said cylindricalmember.

3. A drafting pen comprising a strip of sheet metal tapered at its endsto provide nibs and being of substantially uniform thickness throughouttheremainder of its length, a cylindrical spool having peripheralflanges at its ends, said strip having its mid-portion looped'about saidspool between said flanges, adjustable means intermediate said spool andsaid nibs for controlling the spacing of said nibs, a handle, and meansfor retaining said spool within the loop of said strip and securing saidstrip to said handle.

4. A drafting pen comprising a strip of sheet metal looped at itsmid-portion about a cylindrical member and tapered at its ends toprovide nibs, said strip being of substantially uniform thicknessthroughout the remainder of its length, and a handle including fasteningmeans extending through an opening in the looped midportion of saidstrip and into said cylindrical member.

FLOYD G. EUBANKS.

